Strange issue - ETC,TracCntrl,Ck Eng lights on. Jeep runs fine..almost!

So here’s the deal, as short as I can. One day, Jeep runs perfect. Next morning, start it up and my dash looks like Christmas. ETC, Traction Control, Check Engine and TPMS lights, all on. TPMS, easy fix. FYI - this is 2012 Jeep Wrangler JKU AUTO, w/ 84,000 miles, 2 1/2 lift, on 35x12.5x20 Maxxis Bighorn mud tires. (Quick shout out to Maxxis. I literally have put ALL 84,000 miles on these tires, and they still have enough tread left to pass inspection! WTH!!). Back to the issue. In my research, I’ve heard horror stories of other Jeep’s with this issue having to limp home, Jeeps just stalling out, running bad, etc. And then, hearing about multiple trips and LOTS of dollars thrown at it, and still not fix the issue. But here’s the thing. The Jeep, basically runs perfect. No hesitation, no spitting and sputtering, no stalls. Will easily maintain 30mph, or 75mph on the highway for as far as 100 miles so far. The ONLY issues I have found to date are, (1) one - it will not go into Cruise Control, (2) two - it will not shift to 5th on its own. So if I’m going down the highway in 4th, I can manually downshift and then manually upshift to 5th, and that works. (3) three - when trying to accelerate to pass, it will not kick down a gear for more rpms to pass someone. Again, I can do it manually, but not on its own like it should. Otherwise, shifts up and down like it should on auto, and no other noticeable concerns. Even MPG is the same. Like I said, I cannot afford to throw money at it, hoping something works. FYI (2)-New oil change, new gas etc, as preemptive strikes. Also it does show - P520, P300 codes. I do strongly believe, it’s not something with those codes:Thanks
You. does anyone out there have any thoughts, ideas, heard of this, “like” this, solutions, etc. ??? I would really appreciate some advice and/or direction. Thanks.


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First thoughts are that the shift issue may be s response to the codes.

Generic checks.
1. Load test battery
2. Clean battery terminals and ground contacts at engine and chassis.
3. Reset the codes and see if they return.

If they do. Report back.

What weight oil did you use?
Low level or too thin oil can cause this fault.


Never look down on anyone unless you are helping them up - Jesse Jackson
 
2nd thought on shifting. Did you correct speedo for any tire & gear changes?
CPK, speedo and CPS need to agree.

P0300 is generic misfire code.
Again reset codes and see if they return.


Never look down on anyone unless you are helping them up - Jesse Jackson
 
2nd thought on shifting. Did you correct speedo for any tire & gear changes?
CPK, speedo and CPS need to agree.

P0300 is generic misfire code.
Again reset codes and see if they return.


Never look down on anyone unless you are helping them up - Jesse Jackson

Yes, speedo, etc corrected. I saw the “results” of P300. However, if it were actually misfiring, it wouldn’t run as smooth as it does. You’d feel it of course.

Oil was just changed after problem presented, so that’s not it.

I tried computer reset with no luck

Got a call into local shop where all they work on is Jeep’s. Very knowledgeable and good people. Supposed to c/b soon, so we’ll see.

Thanks though. Any other thoughts, I’d love to hear it.


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P0300 is general misfire. P0301 is cylinder 1. 302 is cyl 2... So you may have knock. Might check your plugs and run some injector cleaner and new air filter. Clean TB and IAC. Tire pressure?
How does the trans fluid look?

Mentioned battery cause bad battery or connections result in phantom codes.

Never look down on anyone unless you are helping them up - Jesse Jackson
 
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What gear ratio and tire size?
Any changes before this started to happen?


Regards,
JPNinPA

Never look down on anybody unless you're helping them up. -Jesse Jackson
 
What gear ratio and tire size?
Any changes before this started to happen?


Regards,
JPNinPA

Never look down on anybody unless you're helping them up. -Jesse Jackson

The tires are 35x12.5x20 Maxxis Bighorn Mud tires. I thought I mentioned that in the original comment. Also, HUGE shout out to Maxxis for these tires going 84,000 miles and still going. NEVER heard of a mud tire getting that much mileage out of ‘em. As far as the gears, I’m not sure. I bought the Jeep “used” with 2400 miles on it. So basically brand new. The dealership did the lift/tires, etc, so I, not sure. I’ll figure it out and get back to you.


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Yeah you did mention tire size.
Still want help?


Never look down on anyone unless you are helping them up - Jesse Jackson
 
Hey, I’ll take any thoughts or advice I can get. I did check on the gearing. From best I can tell with the charts available, as this is the 3.6 Pentastar 5-speed Auto w/ OD, it leans towards 4.10 gears, but I seriously doubt the dealer went from stock 3.73 to that. So, it probably has just the stock 3.73’s. I should have 4.56, if not even 4.88, as most of my driving is hwy. But until I find someone who wants to give me a set and install them, simply because I’m a nice guy, that won’t be soon. However, if for some reason you think they might add to the issue, my question is then , “why”? After driving this Jeep daily for the past 8 years with no issues, why all of a sudden?


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Did some searching and stock was 3.07 or 3.73. The taller gears gave had issues with 35s and going into 5th

You may have been on the edge for 8 years and a few things changed slightly.

Looking to see if the. Trans shifts based on rpm, speed, tps cpk cps...


Never look down on anyone unless you are helping them up - Jesse Jackson
 
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